53. •••

(a) Find the individual monthly (30-day) electric energy costs (to the nearest dollar) for each of the following household appliances if the utility rate is

$0.12/kWh: central air conditioning that runs 30%

of the time; a blender that is used 0.50 h/month; a dishwasher that is used 8.0 h/month; a microwave oven that is used 15 min/day; the motor of a frost-free refrigerator that runs 15% of the time; a stove (burners plus oven) that is used a total of 10 h/month; and a television that is operated 120 h/month.

(b) Determine the percentage that each appliance contributes to the total monthly electric cost.

(c) What is the resistance of each appliance and current in each appliance when they are operating? (You may find useful information in Table 17.2.)